Device for sand-blasting bores



Sept. 6, 1960 F. KORNHAUS 2;951,319

DEVICE FOR SAND-BLASTING BORES I Filed July 1, 1957 2 Sheets-Sheet 1 INVENTOR.

Sept. 6, 1960 F. l. KORNHAUS DEVICE FOR SAND-BLASTING BORES 2 SheetsSheet 2 Filed July 1, 1957 INVENTOR. FLOYD I. KORNHHMS 71am A rroa 1s United States Patent DEVICE FOR SAND-BLASTING BORES Floyd I. Kornhaus, 2445 66th Ave, Oaklmd 5, Calif.

Filed July 1, 1957, Ser. No. 669,022

Claims. (Cl. 51-8) The invention relates to a device for cleaning a coating from a cylindric bore by the forcible application of abrasive particles against it.

Recalling that variously disposed and utilized pipes or the like may acquire deleterious coatings in their bores, a present general object is to provide a sand-blasting head which is applicable to the progressive removal of such coatings from bores in a particularly eifective manner.

Another object is to provide a sand-blasting head which is particularly designed for the cleaning of such bores as those of upright stack and standpipe structures while the same are installed for their use.

A further object is to provide for the adjustable support of a present sand-blasting head in centered relation to a bore being cleaned.

An added object is to provide for an oscillatory operation of the nozzle of the head.

Yet another object is to provide for the delivery of liquid into a relatively dry abradant as it is discharged from the nozzle. 7

The invention possesses other objects and features of advantage which, with the foregoing, will be set forth or be apparent in the following description of a typical embodiment thereof, and in the accompanying drawings, in which,

Figure 1 illustrates a head embodying the features of invention and operatively installed within a fragmentarily shown upright pipe.

Figure 2 is a plan view taken from the line 2-2 in Figure 1.

Figure 3 is an enlarged axial section of the head.

Figure 4 is an enlarged side view of a head-centering unit of the assembly.

Figure 5 is an enlarged and partly sectional showing of a swivel connection between the head and a hose for supplying abradant to the head.

Figure 6 is an enlarged fragmentary view taken from the line 6-6 in Figure 1.

Figure 7 is a fragmentary view taken from the broken line 77 in Figure 6.

Figure 8 is an enlarged fragmentary section taken at a nozzle portion of the head.

Figure 9 is an enlarged fragmentary view taken adjacent the line 9-9 in Figure 3.

Figure 10 is a fragmentary elevation of the showing of Figure 9.

Figure 11 is an enlarged fragmentary side elevation of the lower support connections for the nozzle of the head.

Figure 12 is an underneath view of the structure of Figure 11.

The present device has been particularly designed for cleaning the bores of such tubular structures as stacks and flues and standpipes and the like while the same are in upright use positions thereof, such structures being represented by the illustrated upright pipe P having a uniform bore B to be cleaned. As shown, the features of my invention are provided in a unitary working head assembly 15 which is arranged for its progressive lowering in the pipe P while carried from its top by a flexible support cable or line L which depends from a suitable winch, or the like, not shown. The head assembly 15 includes a lower pipe section 16 carrying a nozzle at its forward (lower) end discharging obliquely forwardly with respect to the pipe axis, and the pipe section 16 carrying the head 15 is arranged to comprise the lower section of an abradant-supplying pipe assembly of appropriate length which is long enough to extend above the top of a pipe P while the head is being lowered through the pipe bore B. Any required number of pipe sections 17 may be utilized above the nozzle-carrying section 16, and the uppermost section 17 is attached at its top through a quick-release coupling 18 and a tubular swivel connection 19 with a hose H through which the abradant is arranged to be supplied under appropriate pressure from a suitable source, not shown. Adjacent its nozzle end, the pipe section 16 is directly carried by a support unit or carriage 20 in swiveled relation thereto, with said unit including a base member 21 of uniform angle section and having bearing sleeves 22 journalling the pipe section 16 and fixed to and within it, as by welding, at the ends of the trough defined by its flanges 21 which extend from a common exterior edge 21" of the member21.

The bearings 22 rotatably receive a major intermediate portion of the pipe section 16 in and between them, and said pipe section fixedly carries upper and lower collars 23 and 24 respectively disposed outwardly of and adjacent the sleeves 22 for providing a constantly retained and swiveled mounting of the pipe 16 in the bearings 22, whereby the, engaged pipe 16 may be rotated or oscillated with respect to the member 21 while the latter supports the pipe thereon. At the upper end thereof, the member 21 of the support unit 19 is provided with an upwardly-directed carrying member 25 of U-bend structure having its ends fixed to the base member flanges 21' at their outer sides, as by welding, said member providing an elongated loop which freely spans the pipe 16 at the adjacent collar 23 thereon, while the bight 25' of its loop receives the bight of a clevis 26 having its pin 26' engaged through a terminal eye L of the hoist line L. The arrangement is essentially such that the member 21 and its supported pipe section 16 may be adjustably carried by and from the support line L while disposed in a pipe P being cleaned.

It will be noted that the lowerportion of the pipe member 16 extends appreciably below the lower collar 24 and threadedly mounts a reducing nipple 27- having one end threadedly mounted on the pipe extremity and the other end threadedly engaged in one end of an elbowfitting 28 having an angle of the order of 45, said fitting receiving an end of a jet tube 29 of an abradant-discharging nozzle 31 at its other end. Noting, by particular reference to Figures 3 and 8, that the curved bore portion of the elbow-fitting 28 between the extremities of the pipe 16 and the tube 29 engaged therein is generally uniform and appreciably larger than the bores of the connected pipe and jet tube, and is particularly subject to the abrasive action of the abradant stream therethrough by reason of the change of direction forced-upon the stream therein, a means is preferably provided for minimizing wear in said fitting. Accordingly, and as illustrated, a tubular lining member 32 of a suitable non-metallic wear-resistant material is preferably engaged between the opposed pipe and tube ends for appreciably prolonging the life of the elbow fitting; a lining member of neoprene has been found particularly durable for the present purpose.

As is particularly brought out'in Figures 1 and 3 and 3 8, the nozzle 31 includes a generally tubular body 33 carried on the rearward part of a threaded jet tube portion 29' arranged for its stopped sealed engagement in the forward end of the elbow fitting 28 and having its forward part threadedly engaging an enlarged threaded rear part of the bore 34 of the body 33 extending from an annular seat 35 which is arranged for its flat engagement as a sealing stop by the forward end of said threaded part 29 of the jet tube 29, the arrangement being essentially such that said threaded tube part is operative as a connecting nipple between the body 33 and the elbow fitting 28, the jet tube 29 being thus replaceable. The bore 36 of the jet tube 29 is symmetrica-lly contracted from its inner end where it registers with the bore of the lining member 32 of the elbow fitting 28, and the tube 29 may, as shown, terminate rearwardly of the forward body face 37 and within a forward expanded portion of the body bore 34.

Means are provided for discharging a liquid with or into the delivered jet, and the nozzle body element 33 is accordingly formed to provide within it a continuous circular manifold chamber 38 coaxial with its bore and having a plurality of discharge ports 39 extending from it to the forward body face 37 to provide for the pressure discharge of a circular line of liquid jets into the jet of a stream of abradant emitted from the jet tube 29. At a side point thereof, the body 33 is provided with a radial extension 41 which provides a supply duct 42 leading from a hose connection 43 at the rear face of the extension 41 to the manifold chamber 38. A flexible hose 44 extends to the connection 43 from a connection 45 at the forward end of a rigid pipe or tube 46 which extends through the trough of the base member 21 between the pipe section 16 therein and the trough bottom in fixed relation to the member, and a hose connection 47 is provided at the extending rearward end of the pipe 46 for the attachment thereat of a liquid-supply hose 48 extending adjacent and along the portion of the support line L within the pipe P. It will be noted that the liquid discharged from the nozzle ports 39 would usually, but not necessarily, be water, and may function, for instance, to moisten the applied abradant while serving as a sparkarresting and dust-suppressing means at the working point.

The uppermost pipe section 17 connected to the nozzlecarrying pipe 16 is utilized for oscillating the pipe assembly about the pipe axis while the assembly is held positioned by the support line L, it being noted that the section 16 and any intermediate pipe sections 17 above it are connected in order by usual threaded pipe coupling 49 whereby the utilized pipes 17 functions as a unitary part of the head assembly which is oscillatable about the pipe axis to apply the working jet from the nozzle 31 through an angle which is no less than 360. Accordingly, and as shown, a hand wheel 51 is replaceably and removably mounted on the uppermost section 17 by means of a clamp assembly 52 which secures the hub of the wheel 51 to the engaged pipe section 17. As particularly brought out in Figure 2, the pipe 17 is arranged to be compressedly gripped by and between opposed jaw recesses provided by members 53 and 54 which are mutually hinged at one end and are operative as clamp members through the action of a bolt 55 operative between their other ends, it being noted that the member 53 comprises the sole spoke for the wheel rim 56 which is discontinuous at a point opposite the spoke member 53 to facilitate the disposal of the support line L and the liquid supply hose 47 to constantly and displaceably extend adjacent the axis of the head assembly.

Owing to the connection of the nozzle 31 to the liquidsupplying pipe 46 by means of the hose 44 of necessarily limited length, a means is provided to limit the oscillatory movements of the pipe section 16 between limiting positions through an assured three hundred sixty degree (360) working application of a jet from the nozzle. Accordingly, and as brought out in Figures 11 and 12, the

lower end of the base member 21 mounts a depending ear 57 provided with a uniform slot 58 which extends perpendicularly to the axis of the working head, and slidably receives the shank 61 of a stop pin comprising a bolt 59 having its head 62 at its radially inner end and mounting a nut 63 at its other end for cooperation with the bolt in the slot 58 to retain the bolt in the slot for its shifting along the slot. A collar 64 fixed to the pipe section 16 below the base member 21 provides a radial stop projection 65 for oscillation with the pipe to alternatively move against the head 62 of the shiftable pin 59 in limiting oscillated positions of the pipe, it being understood that the permitted movement of the pin 59 along the slot 58 by the action of the projection 65 provides for the rotation of the collar 64 through an angle of not less than three hundred sixty degrees (360), and thereby permits the required oscillation of the nozzle while the base member 21 is held against rotation about its longitudinal line, the hose 44 being of appropriate length to permit such an oscillatory nozzle movement.

The centering means for the support carriage 20 for the pipe section 16 essentially comprises spaced sets of centering arms 66 and 67 and 68 radiating from the base member 21 adjacent the opposite ends thereof and terminally mounting wheels 69 which are rotatable about axles 69' provided at the arm ends in perpendicular relation to the longitudinal axis of the nozzle-carrying pipe section 16. As particularly illustrated, the arms 66 and 67 of each set are hinged to ears 71 extending from the outer sides of the different flanges 21 of the member 21 for their swinging adjustments in planes parallel to their associated flanges about hinge pins 72 connecting them with the ears. Ears 73 extend externally from the angle-iron head-supporting member 21 at points thereof adjacent the corner edge 21" of the member, with said ears having the arms 68 hingedly attached thereto by hinge pins 74 for a swinging adjustment of the arms 68 in a plane parallel to the bisecting plane of the flange angle which is shown as of ninety degrees.

It will now be noted that the centering arms 66 and 67 and 68 essentially comprise bars respectively receiving through inner ends thereof the hinge pins 72 and 72 and 74 by which the arms are respectively connected to the ears 71 and 71 and 73. Outwardly of the hinge pins 72, the arms 66 and 67 fixedly mount plates 75 providing sets of holes 76 for receiving bolts 77 which are arranged to selectively engage transverse holes 78 provided along the opposed flanges 21' of the member 21 adjacent the outer edgesthereof for securing the arms in angularly adjusted relation to the axis of the supported head member 16. Positioning plates 79 for cooperative use with the arms 68 extend fixedly from the corner 21" of the member 21 in the bisecting plane of the member angle, and are provided with sets of holes 81 which are arranged to selectively receive securing bolts 82 which are engageable through holes provided in the arms 68 and selectively registerable with the holes 81 to provide for set adjustments of the angularity of the latter arms to th member 16.

Noting that the present arm-positioning arrangement is essentially such that the wheels 69 may be adjustably and substantially equally spaced from the longitudinal line of the member 16 to provide for a centered and guided fitting of the member 21 in an upright bore B to be cleaned, it will be understood that the bore-engaging wheels 69 are generally operative to prevent a rotation of the headsupporting assembly of the member 21 while the head is being operatively oscillated in a bore B. Since, however, bores to be cleaned may be out-of-round and/ or of vary ing diameter along them, at least one aligned pair of armcarried wheels 69 is desirably arranged for its inward deflection against resiliently yielding resistance, and such an arrangement is disclosed for the wheels 69 of the arms 68. As particularly indicated in Figure 3, the Wheel 69 of each arm 68 is carried at the outer end of an outer arm section 68' hingedly attached at a hinge pin 84 to the outer end of the inner arm section 68" for a limited swinging of the section 68 against spring resistance from a normal position in which its inner end normally engages a stop extending transversely from the inner arm section 68", said spring resistance being shown as provided by a tension spring 86 which appropriately connects the inner end of the arm section 68 with an anchorage provided on the arm section 68; with this arrangement, the centering engagement of the set of wheels 69 with an engaged bore may be maintained as the present head assembly moves through the bore.

Having the present working-head assembly 15 adjustably supported by a line L in an upright pipe P in centered relation to the pipe bore while it is connected with a source of more or less dry abradant through the extension pipe 17 and the swivel 18 and the supply hose H, it will be understood that the head may be progressively moved along the pipe bore by raising and lowering it therein while it is oscillated about its axis by an operator utilizing the hand wheel 51. Since the use of a present sand-blasting head 16 in longer pipes P will require the use of more or fewer pipe sections 17 as the head is respectively lowered or raised in the pipe, a means is provided for facilitating the addition or subtraction of pipe sections 17 as required. Accordingly, and as is particularly brought out in Figures 1 and 2 and 6 and 7, a temporary support for the assembly of the pipes 16 and 17 is provided, and said support essentially comprises a cross-bar 88 arranged to span and rest upon the top edge of the pipe P While non-rotatively supporting the portion of the pipe assembly disposed below it.

As particularly shown, the support bar 88 intermediately provides a clamp assembly 89 for engaging a pipe section 17 at a point thereof adjacent and above the top edge of the pipe P, whereby the engaged pipe section 17 may non-rotatively support the assembly beneath it while pipe sections 17 may be added to or subtracted from the head-supporting pipe sections 17 depending from the bar 88 and below a coupling 49 disposed above the point of support. The present clamp assembly 89 provides opposed jaws comprising cooperative half-sleeve members 90 and 91 respectively mounted on a base member 92 fixed to the bar, as by welding, and a clamp plate 93 receiving therethrough bolts 94 extending fixedly from the base member 92 and mounting hand nuts 95 outwardly of the plate. If desired, the support bar 88 may be provided with sets of holes 96 which extend parallel to the axis of clamping of the clamp assembly 89 and are arranged to selectively receive pins 97 to depend within the top of the pipe bore for maintaining a centering of the clamp assembly 89 While it is supported on and across the top end of the pipe.

When the number of pipe sections 17 in a working-head assembly is to be increased or decreased, the hose H is disconnected from the uppermost pipe section 17 at the coupling 18, and the working-head assembly is supported on the line L until the support bar 88 has been operatively fixed to it. If a section 17 is to be added to a pipe assembly 16-17, the uppermost section 17 of the assembly is disposed with its coupling-receiving upper end adjacent and above the top of the pipe P, the support bar 88 is then clamped to the pipe just below said upper end of the upper section, the additional section 17 is connected in place by the use of a coupling 49, and the added-to pipe assembly is then released from its mounted relation to the support bar 88 for its lowering by the line L and its re-connection with the hose H through the coupling 18.

If a pipe section 17 is to be removed from a pipe assembly 1617, the hose H is disconnected from the upper end of the assembly, said pipe assembly is then raised by the line L until the next lower section 17 extends above the top of the pipe P, the mounted support bar 88 is clamped to the latter pipe section, and the upper pipe section 17 is then released by unscrewing it to pro vide for a re-couplin-g of the hose H with the section directly engaged by the bar 88. It will be noted that the bar 88 may remain in place on the top of the pipe while the clamp 89 is inoperative by reason of a loosening of the nuts 95, whereby the bar may be constantly available for an emergency gripping and support of the pipe assembly thereat aside from its use during any change in the number of sections 17 being utilized in the head assembly.

One or more auxiliary pipe-centering assemblies may be advantageously provided and utilized in an assembly comprising a section 16 and a plurality of the pipe sections 17 for maintaining the alignment of the installed said sections with each other and with the attached nozzle-carrying section 16. As particularly illustrated in Figures 1 and 4, an assembly has the pipe-centering features of the member 21 of the unit 28 which receives the pipe section "16 in swiveled relation to it and provides centering arms mounted on a base member 121 of angle section having pipe-receiving bearing sleeves 122 fixed in the ends of its trough. The flanges 121' of the base member 121 hingedly mount pairs of centering arms 166 and 167 which correspond to the arms 66 and 67 or the nozzle-carrying assembly 19, and terminally carry wheels 169 for engaging the bore of a pipe being cleaned, with the angular relation of said arms to the axis of an engaged pipe section 17 adjustably settable by the use of transversely perforated positioning plates carried by the arms 166 and 167, which arms are arranged for their adjusted positioning by the use of bolts 177 selectively cooperative between mutually registerable holes in the plates 175 and in the difierent flanges 121' which mount the arms. A single arm 168 corresponding to an arm 68 of the centering assembly of the unit 20 has 'its inner end hingedly attached to the member 121 at its corner edge 121" and is cooperative with an opposed plate 179 mounted on the member 121 for an adjusted setting of this arm by the use of a bolt 182 which is cooperative between selectively registerable transverse holes in the plate and the opposed arm portion.

When a present pipe-centering assembly 120 is to be used, it is mounted on an upright pipe section 17 of a present head assembly 15 with its bottom pipe-receiving sleeves 122 seated on the pipe coupling 49 which engages thebottom of the received section, whereby it is then supported by the pipe assembly for the rotation of the head assembly While it non-rotatively engages the bore being cleaned; the number of centering assemblies 120 to be utilized in this manner is determined by the overall length and operating conditions at a line of pipes 17.

While the complete present assembly has been particularly designed for use in cleaning the bores of upright ducts of such structures as lines and standpipes, it may also be used for cleaning more-or-less horizontally disposed bores; in the latter case, the connected assembly of pipe sections 17 extending from the nozzle-providing section 16 would be used as a push-and-pull positioning means in lieu of a support line L, with an appropriate number of the auxiliary centering assemblies 120 then being utilized.

From the foregoing description taken in connection with the accompanying drawings, the advantages of the present device for sandblasting bores will be readily understood by those skilled in the art to which the invention appertains. While I have shown and described a structure and arrangement which I now consider to be a preferred embodiment of my invention, I desire to have it understood that the showings are primarily illustrative, and that such changes and developments may be made, when desired, as fall within the scope of the following claims.

I claim:

1 In a unitary sand-blasting head arranged for its progressive coating-removing operation along the coated bounding surface of a substantially uniform upright bore which is open at its top and defines a duct for normally conveying a stream of a fluid therethrough, a pipe for carrying a stream containing an abradant material and extending axially into said duct from above the duct top and fixedly carrying a discharge nozzle at the lower end thereof for directing a jet of the abrasive therefrom toward the bore-defining surface, a pipe-support member movable along and within the duct and oscillatively carrying the pipe in swiveled coaxial relation thereto and in centered relation to the duct bore, means operative through the duct carrying the support member from above for the progressively adjusted positioning of said nozzle along the bore, and means connecting the upper end of the pipe with a source of the abradant stream.

2. A sand-blasting head in accordance with claim 1 for which the abradant source comprises a flexible hose connected to the top of the pipe and containing fluidcarried abrasive particles, a swivel joint connects the pipe with the hose, and the means for effecting an adjusted positioning of the pipe along the duct bore comprises a flexible support line depending freely in the duct bore from the upper end of the bore to a connection with the support member.

3. A sand-blasting head in accordance with claim 1 in which the support member provides radial arms cooperative with the duct-defining surface to center the pipe assembly therein while restraining the support member against rotation in the bore, and a hand-wheel is mounted on tl e pipe above the open upper duct end for its actuation to oscillate the pipe assembly in the duct bore for variably directing the nozzle jet against the duct bore circumferentially thereof.

4. A structure in accordance with claim 1 wherein the nozzle replaceably provides a single jet tube, said jet tube directly carries on encircling manifold providing discharge ports for delivering an abradant-wetting liquid in a plurality of streams which mutually intersect at the axis of the stream discharged from the jet tube, and a 8 flow tube traversing the duct provides the liquid supplied to the manifold.

5. In a unitary sand-blasting head arranged for a progressive de-coating operation thereof against and along the bounding surface of an upright bore which is open at its top and defines a duct depending from a transverse bounding support surface at its top and arranged to normally convey a fluid stream containing a material with which the duct-defining surface has become coated, a pipe structure comprising one or more sections for carrying a stream containing an abradant material and extending axially into said tube from and above said support surface at the duct top and fixedly mounting an abradantdischarge nozzle at its lower end for directing a jet of the abrasive therefrom toward the bore-defining surface, a pipe-support member movably disposed within the duct and carrying the nozzle-mounting section in swiveled coaxial relation thereto and in centered relation to the duct bore, a flexible cable means carrying the support member from above for the adjusted gravity positioning of said nozzle along hte bore, means mounted on the upwardly extending pipeportion and cooperative with said support surface at the top of the duct to fixedly support the extending pipe portion in supported relation to said support surface during the addition or subtraction of a pipe section to and above it, and means releasably connecting the upper end of the uppermost section of the pipe assembly with a source of the abradant stream whereby the stream source may be disconnected from the pipe during the removal or addition of a pipe section.

References Cited in the file of this patent UNITED STATES PATENTS Swenarton Oct. 16, 1945 

